Thanks for your replies. It seems I was too hasty in checking my earnings report (1st day of the Month) as it has now been adjusted and the deduction has been amending, meaning I should get my payments in full for April and June, without the negative balance for May being deducted. This casino does not have negative carryover so I knew this could not be right.
As for the one pound CPA, yes it is definately CPA. They offer it as standard I think, however its worthless when they keep taking it back when my account ends the month with negative balance, as is happening more frequently.
I queried this once before with one of the Affiliate managers, and they just said its standard practice to take back the CPA if your account goes into negative balance. It may well be standard practice, but in my mind it is theft.
This casino is licenced in Gibralter. I am thinking to make a complaint to the licencing authority about it. Or you have any better ideas?